diff options
Diffstat (limited to 'mm/slub.c')
| -rw-r--r-- | mm/slub.c | 506 |
1 files changed, 373 insertions, 133 deletions
diff --git a/mm/slub.c b/mm/slub.c index 5cc4b7dddb5..e2989ae243b 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -149,6 +149,13 @@ static inline void ClearSlabDebug(struct page *page) /* Enable to test recovery from slab corruption on boot */ #undef SLUB_RESILIENCY_TEST +/* + * Currently fastpath is not supported if preemption is enabled. + */ +#if defined(CONFIG_FAST_CMPXCHG_LOCAL) && !defined(CONFIG_PREEMPT) +#define SLUB_FASTPATH +#endif + #if PAGE_SHIFT <= 12 /* @@ -243,13 +250,25 @@ enum track_item { TRACK_ALLOC, TRACK_FREE }; static int sysfs_slab_add(struct kmem_cache *); static int sysfs_slab_alias(struct kmem_cache *, const char *); static void sysfs_slab_remove(struct kmem_cache *); + #else static inline int sysfs_slab_add(struct kmem_cache *s) { return 0; } static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p) { return 0; } -static inline void sysfs_slab_remove(struct kmem_cache *s) {} +static inline void sysfs_slab_remove(struct kmem_cache *s) +{ + kfree(s); +} + #endif +static inline void stat(struct kmem_cache_cpu *c, enum stat_item si) +{ +#ifdef CONFIG_SLUB_STATS + c->stat[si]++; +#endif +} + /******************************************************************** * Core slab cache functions *******************************************************************/ @@ -277,15 +296,32 @@ static inline struct kmem_cache_cpu *get_cpu_slab(struct kmem_cache *s, int cpu) #endif } +/* + * The end pointer in a slab is special. It points to the first object in the + * slab but has bit 0 set to mark it. + * + * Note that SLUB relies on page_mapping returning NULL for pages with bit 0 + * in the mapping set. + */ +static inline int is_end(void *addr) +{ + return (unsigned long)addr & PAGE_MAPPING_ANON; +} + +void *slab_address(struct page *page) +{ + return page->end - PAGE_MAPPING_ANON; +} + static inline int check_valid_pointer(struct kmem_cache *s, struct page *page, const void *object) { void *base; - if (!object) + if (object == page->end) return 1; - base = page_address(page); + base = slab_address(page); if (object < base || object >= base + s->objects * s->size || (object - base) % s->size) { return 0; @@ -318,7 +354,8 @@ static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp) /* Scan freelist */ #define for_each_free_object(__p, __s, __free) \ - for (__p = (__free); __p; __p = get_freepointer((__s), __p)) + for (__p = (__free); (__p) != page->end; __p = get_freepointer((__s),\ + __p)) /* Determine object index from a given position */ static inline int slab_index(void *p, struct kmem_cache *s, void *addr) @@ -354,22 +391,22 @@ static void print_section(char *text, u8 *addr, unsigned int length) printk(KERN_ERR "%8s 0x%p: ", text, addr + i); newline = 0; } - printk(" %02x", addr[i]); + printk(KERN_CONT " %02x", addr[i]); offset = i % 16; ascii[offset] = isgraph(addr[i]) ? addr[i] : '.'; if (offset == 15) { - printk(" %s\n",ascii); + printk(KERN_CONT " %s\n", ascii); newline = 1; } } if (!newline) { i %= 16; while (i < 16) { - printk(" "); + printk(KERN_CONT " "); ascii[i] = ' '; i++; } - printk(" %s\n", ascii); + printk(KERN_CONT " %s\n", ascii); } } @@ -470,7 +507,7 @@ static void slab_fix(struct kmem_cache *s, char *fmt, ...) static void print_trailer(struct kmem_cache *s, struct page *page, u8 *p) { unsigned int off; /* Offset of last byte */ - u8 *addr = page_address(page); + u8 *addr = slab_address(page); print_tracking(s, p); @@ -529,7 +566,7 @@ static void init_object(struct kmem_cache *s, void *object, int active) if (s->flags & __OBJECT_POISON) { memset(p, POISON_FREE, s->objsize - 1); - p[s->objsize -1] = POISON_END; + p[s->objsize - 1] = POISON_END; } if (s->flags & SLAB_RED_ZONE) @@ -558,7 +595,7 @@ static void restore_bytes(struct kmem_cache *s, char *message, u8 data, static int check_bytes_and_report(struct kmem_cache *s, struct page *page, u8 *object, char *what, - u8* start, unsigned int value, unsigned int bytes) + u8 *start, unsigned int value, unsigned int bytes) { u8 *fault; u8 *end; @@ -648,7 +685,7 @@ static int slab_pad_check(struct kmem_cache *s, struct page *page) if (!(s->flags & SLAB_POISON)) return 1; - start = page_address(page); + start = slab_address(page); end = start + (PAGE_SIZE << s->order); length = s->objects * s->size; remainder = end - (start + length); @@ -682,9 +719,10 @@ static int check_object(struct kmem_cache *s, struct page *page, endobject, red, s->inuse - s->objsize)) return 0; } else { - if ((s->flags & SLAB_POISON) && s->objsize < s->inuse) - check_bytes_and_report(s, page, p, "Alignment padding", endobject, - POISON_INUSE, s->inuse - s->objsize); + if ((s->flags & SLAB_POISON) && s->objsize < s->inuse) { + check_bytes_and_report(s, page, p, "Alignment padding", + endobject, POISON_INUSE, s->inuse - s->objsize); + } } if (s->flags & SLAB_POISON) { @@ -692,7 +730,7 @@ static int check_object(struct kmem_cache *s, struct page *page, (!check_bytes_and_report(s, page, p, "Poison", p, POISON_FREE, s->objsize - 1) || !check_bytes_and_report(s, page, p, "Poison", - p + s->objsize -1, POISON_END, 1))) + p + s->objsize - 1, POISON_END, 1))) return 0; /* * check_pad_bytes cleans up on its own. @@ -715,7 +753,7 @@ static int check_object(struct kmem_cache *s, struct page *page, * of the free objects in this slab. May cause * another error because the object count is now wrong. */ - set_freepointer(s, p, NULL); + set_freepointer(s, p, page->end); return 0; } return 1; @@ -749,18 +787,18 @@ static int on_freelist(struct kmem_cache *s, struct page *page, void *search) void *fp = page->freelist; void *object = NULL; - while (fp && nr <= s->objects) { + while (fp != page->end && nr <= s->objects) { if (fp == search) return 1; if (!check_valid_pointer(s, page, fp)) { if (object) { object_err(s, page, object, "Freechain corrupt"); - set_freepointer(s, object, NULL); + set_freepointer(s, object, page->end); break; } else { slab_err(s, page, "Freepointer corrupt"); - page->freelist = NULL; + page->freelist = page->end; page->inuse = s->objects; slab_fix(s, "Freelist cleared"); return 0; @@ -866,7 +904,7 @@ bad: */ slab_fix(s, "Marking all objects used"); page->inuse = s->objects; - page->freelist = NULL; + page->freelist = page->end; } return 0; } @@ -891,24 +929,22 @@ static int free_debug_processing(struct kmem_cache *s, struct page *page, return 0; if (unlikely(s != page->slab)) { - if (!PageSlab(page)) + if (!PageSlab(page)) { slab_err(s, page, "Attempt to free object(0x%p) " "outside of slab", object); - else - if (!page->slab) { + } else if (!page->slab) { printk(KERN_ERR "SLUB <none>: no slab for object 0x%p.\n", object); dump_stack(); - } - else + } else object_err(s, page, object, "page slab pointer corrupt."); goto fail; } /* Special debug activities for freeing objects */ - if (!SlabFrozen(page) && !page->freelist) + if (!SlabFrozen(page) && page->freelist == page->end) remove_full(s, page); if (s->flags & SLAB_STORE_USER) set_track(s, object, TRACK_FREE, addr); @@ -947,7 +983,7 @@ static int __init setup_slub_debug(char *str) /* * Determine which debug features should be switched on */ - for ( ;*str && *str != ','; str++) { + for (; *str && *str != ','; str++) { switch (tolower(*str)) { case 'f': slub_debug |= SLAB_DEBUG_FREE; @@ -966,7 +1002,7 @@ static int __init setup_slub_debug(char *str) break; default: printk(KERN_ERR "slub_debug option '%c' " - "unknown. skipped\n",*str); + "unknown. skipped\n", *str); } } @@ -1005,7 +1041,7 @@ static unsigned long kmem_cache_flags(unsigned long objsize, */ if (slub_debug && (!slub_debug_slabs || strncmp(slub_debug_slabs, name, - strlen(slub_debug_slabs)) == 0)) + strlen(slub_debug_slabs)) == 0)) flags |= slub_debug; } @@ -1039,7 +1075,7 @@ static inline unsigned long kmem_cache_flags(unsigned long objsize, */ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) { - struct page * page; + struct page *page; int pages = 1 << s->order; if (s->order) @@ -1100,6 +1136,7 @@ static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node) SetSlabDebug(page); start = page_address(page); + page->end = start + 1; if (unlikely(s->flags & SLAB_POISON)) memset(start, POISON_INUSE, PAGE_SIZE << s->order); @@ -1111,7 +1148,7 @@ static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node) last = p; } setup_object(s, page, last); - set_freepointer(s, last, NULL); + set_freepointer(s, last, page->end); page->freelist = start; page->inuse = 0; @@ -1127,7 +1164,7 @@ static void __free_slab(struct kmem_cache *s, struct page *page) void *p; slab_pad_check(s, page); - for_each_object(p, s, page_address(page)) + for_each_object(p, s, slab_address(page)) check_object(s, page, p, 0); ClearSlabDebug(page); } @@ -1135,8 +1172,9 @@ static void __free_slab(struct kmem_cache *s, struct page *page) mod_zone_page_state(page_zone(page), (s->flags & SLAB_RECLAIM_ACCOUNT) ? NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE, - - pages); + -pages); + page->mapping = NULL; __free_pages(page, s->order); } @@ -1181,7 +1219,7 @@ static __always_inline void slab_lock(struct page *page) static __always_inline void slab_unlock(struct page *page) { - bit_spin_unlock(PG_locked, &page->flags); + __bit_spin_unlock(PG_locked, &page->flags); } static __always_inline int slab_trylock(struct page *page) @@ -1195,19 +1233,15 @@ static __always_inline int slab_trylock(struct page *page) /* * Management of partially allocated slabs */ -static void add_partial_tail(struct kmem_cache_node *n, struct page *page) +static void add_partial(struct kmem_cache_node *n, + struct page *page, int tail) { spin_lock(&n->list_lock); n->nr_partial++; - list_add_tail(&page->lru, &n->partial); - spin_unlock(&n->list_lock); -} - -static void add_partial(struct kmem_cache_node *n, struct page *page) -{ - spin_lock(&n->list_lock); - n->nr_partial++; - list_add(&page->lru, &n->partial); + if (tail) + list_add_tail(&page->lru, &n->partial); + else + list_add(&page->lru, &n->partial); spin_unlock(&n->list_lock); } @@ -1292,11 +1326,12 @@ static struct page *get_any_partial(struct kmem_cache *s, gfp_t flags) * expensive if we do it every time we are trying to find a slab * with available objects. */ - if (!s->defrag_ratio || get_cycles() % 1024 > s->defrag_ratio) + if (!s->remote_node_defrag_ratio || + get_cycles() % 1024 > s->remote_node_defrag_ratio) return NULL; - zonelist = &NODE_DATA(slab_node(current->mempolicy)) - ->node_zonelists[gfp_zone(flags)]; + zonelist = &NODE_DATA( + slab_node(current->mempolicy))->node_zonelists[gfp_zone(flags)]; for (z = zonelist->zones; *z; z++) { struct kmem_cache_node *n; @@ -1335,20 +1370,25 @@ static struct page *get_partial(struct kmem_cache *s, gfp_t flags, int node) * * On exit the slab lock will have been dropped. */ -static void unfreeze_slab(struct kmem_cache *s, struct page *page) +static void unfreeze_slab(struct kmem_cache *s, struct page *page, int tail) { struct kmem_cache_node *n = get_node(s, page_to_nid(page)); + struct kmem_cache_cpu *c = get_cpu_slab(s, smp_processor_id()); ClearSlabFrozen(page); if (page->inuse) { - if (page->freelist) - add_partial(n, page); - else if (SlabDebug(page) && (s->flags & SLAB_STORE_USER)) - add_full(n, page); + if (page->freelist != page->end) { + add_partial(n, page, tail); + stat(c, tail ? DEACTIVATE_TO_TAIL : DEACTIVATE_TO_HEAD); + } else { + stat(c, DEACTIVATE_FULL); + if (SlabDebug(page) && (s->flags & SLAB_STORE_USER)) + add_full(n, page); + } slab_unlock(page); - } else { + stat(c, DEACTIVATE_EMPTY); if (n->nr_partial < MIN_PARTIAL) { /* * Adding an empty slab to the partial slabs in order @@ -1358,10 +1398,11 @@ static void unfreeze_slab(struct kmem_cache *s, struct page *page) * partial list stays small. kmem_cache_shrink can * reclaim empty slabs from the partial list. */ - add_partial_tail(n, page); + add_partial(n, page, 1); slab_unlock(page); } else { slab_unlock(page); + stat(get_cpu_slab(s, raw_smp_processor_id()), FREE_SLAB); discard_slab(s, page); } } @@ -1373,14 +1414,24 @@ static void unfreeze_slab(struct kmem_cache *s, struct page *page) static void deactivate_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) { struct page *page = c->page; + int tail = 1; + + if (c->freelist) + stat(c, DEACTIVATE_REMOTE_FREES); /* * Merge cpu freelist into freelist. Typically we get here * because both freelists are empty. So this is unlikely * to occur. + * + * We need to use _is_end here because deactivate slab may + * be called for a debug slab. Then c->freelist may contain + * a dummy pointer. */ - while (unlikely(c->freelist)) { + while (unlikely(!is_end(c->freelist))) { void **object; + tail = 0; /* Hot objects. Put the slab first */ + /* Retrieve object from cpu_freelist */ object = c->freelist; c->freelist = c->freelist[c->offset]; @@ -1391,11 +1442,12 @@ static void deactivate_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) page->inuse--; } c->page = NULL; - unfreeze_slab(s, page); + unfreeze_slab(s, page, tail); } static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) { + stat(c, CPUSLAB_FLUSH); slab_lock(c->page); deactivate_slab(s, c); } @@ -1467,16 +1519,21 @@ static void *__slab_alloc(struct kmem_cache *s, { void **object; struct page *new; +#ifdef SLUB_FASTPATH + unsigned long flags; + local_irq_save(flags); +#endif if (!c->page) goto new_slab; slab_lock(c->page); if (unlikely(!node_match(c, node))) goto another_slab; + stat(c, ALLOC_REFILL); load_freelist: object = c->page->freelist; - if (unlikely(!object)) + if (unlikely(object == c->page->end)) goto another_slab; if (unlikely(SlabDebug(c->page))) goto debug; @@ -1484,9 +1541,15 @@ load_freelist: object = c->page->freelist; c->freelist = object[c->offset]; c->page->inuse = s->objects; - c->page->freelist = NULL; + c->page->freelist = c->page->end; c->node = page_to_nid(c->page); +unlock_out: slab_unlock(c->page); + stat(c, ALLOC_SLOWPATH); +out: +#ifdef SLUB_FASTPATH + local_irq_restore(flags); +#endif return object; another_slab: @@ -1496,6 +1559,7 @@ new_slab: new = get_partial(s, gfpflags, node); if (new) { c->page = new; + stat(c, ALLOC_FROM_PARTIAL); goto load_freelist; } @@ -1509,6 +1573,7 @@ new_slab: if (new) { c = get_cpu_slab(s, smp_processor_id()); + stat(c, ALLOC_SLAB); if (c->page) flush_slab(s, c); slab_lock(new); @@ -1516,7 +1581,8 @@ new_slab: c->page = new; goto load_freelist; } - return NULL; + object = NULL; + goto out; debug: object = c->page->freelist; if (!alloc_debug_processing(s, c->page, object, addr)) @@ -1525,8 +1591,7 @@ debug: c->page->inuse++; c->page->freelist = object[c->offset]; c->node = -1; - slab_unlock(c->page); - return object; + goto unlock_out; } /* @@ -1539,24 +1604,54 @@ debug: * * Otherwise we can simply pick the next object from the lockless free list. */ -static void __always_inline *slab_alloc(struct kmem_cache *s, +static __always_inline void *slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, void *addr) { void **object; - unsigned long flags; struct kmem_cache_cpu *c; +/* + * The SLUB_FASTPATH path is provisional and is currently disabled if the + * kernel is compiled with preemption or if the arch does not support + * fast cmpxchg operations. There are a couple of coming changes that will + * simplify matters and allow preemption. Ultimately we may end up making + * SLUB_FASTPATH the default. + * + * 1. The introduction of the per cpu allocator will avoid array lookups + * through get_cpu_slab(). A special register can be used instead. + * + * 2. The introduction of per cpu atomic operations (cpu_ops) means that + * we can realize the logic here entirely with per cpu atomics. The + * per cpu atomic ops will take care of the preemption issues. + */ + +#ifdef SLUB_FASTPATH + c = get_cpu_slab(s, raw_smp_processor_id()); + do { + object = c->freelist; + if (unlikely(is_end(object) || !node_match(c, node))) { + object = __slab_alloc(s, gfpflags, node, addr, c); + break; + } + stat(c, ALLOC_FASTPATH); + } while (cmpxchg_local(&c->freelist, object, object[c->offset]) + != object); +#else + unsigned long flags; + local_irq_save(flags); c = get_cpu_slab(s, smp_processor_id()); - if (unlikely(!c->freelist || !node_match(c, node))) + if (unlikely(is_end(c->freelist) || !node_match(c, node))) object = __slab_alloc(s, gfpflags, node, addr, c); else { object = c->freelist; c->freelist = object[c->offset]; + stat(c, ALLOC_FASTPATH); } local_irq_restore(flags); +#endif if (unlikely((gfpflags & __GFP_ZERO) && object)) memset(object, 0, c->objsize); @@ -1591,7 +1686,15 @@ static void __slab_free(struct kmem_cache *s, struct page *page, { void *prior; void **object = (void *)x; + struct kmem_cache_cpu *c; + +#ifdef SLUB_FASTPATH + unsigned long flags; + local_irq_save(flags); +#endif + c = get_cpu_slab(s, raw_smp_processor_id()); + stat(c, FREE_SLOWPATH); slab_lock(page); if (unlikely(SlabDebug(page))) @@ -1601,8 +1704,10 @@ checks_ok: page->freelist = object; page->inuse--; - if (unlikely(SlabFrozen(page))) + if (unlikely(SlabFrozen(page))) { + stat(c, FREE_FROZEN); goto out_unlock; + } if (unlikely(!page->inuse)) goto slab_empty; @@ -1612,21 +1717,31 @@ checks_ok: * was not on the partial list before * then add it. */ - if (unlikely(!prior)) - add_partial_tail(get_node(s, page_to_nid(page)), page); + if (unlikely(prior == page->end)) { + add_partial(get_node(s, page_to_nid(page)), page, 1); + stat(c, FREE_ADD_PARTIAL); + } out_unlock: slab_unlock(page); +#ifdef SLUB_FASTPATH + local_irq_restore(flags); +#endif return; slab_empty: - if (prior) + if (prior != page->end) { /* * Slab still on the partial list. */ remove_partial(s, page); - + stat(c, FREE_REMOVE_PARTIAL); + } slab_unlock(page); + stat(c, FREE_SLAB); +#ifdef SLUB_FASTPATH + local_irq_restore(flags); +#endif discard_slab(s, page); return; @@ -1647,23 +1762,53 @@ debug: * If fastpath is not possible then fall back to __slab_free where we deal * with all sorts of special processing. */ -static void __always_inline slab_free(struct kmem_cache *s, +static __always_inline void slab_free(struct kmem_cache *s, struct page *page, void *x, void *addr) { void **object = (void *)x; - unsigned long flags; struct kmem_cache_cpu *c; +#ifdef SLUB_FASTPATH + void **freelist; + + c = get_cpu_slab(s, raw_smp_processor_id()); + debug_check_no_locks_freed(object, s->objsize); + do { + freelist = c->freelist; + barrier(); + /* + * If the compiler would reorder the retrieval of c->page to + * come before c->freelist then an interrupt could + * change the cpu slab before we retrieve c->freelist. We + * could be matching on a page no longer active and put the + * object onto the freelist of the wrong slab. + * + * On the other hand: If we already have the freelist pointer + * then any change of cpu_slab will cause the cmpxchg to fail + * since the freelist pointers are unique per slab. + */ + if (unlikely(page != c->page || c->node < 0)) { + __slab_free(s, page, x, addr, c->offset); + break; + } + object[c->offset] = freelist; + stat(c, FREE_FASTPATH); + } while (cmpxchg_local(&c->freelist, freelist, object) != freelist); +#else + unsigned long flags; + local_irq_save(flags); debug_check_no_locks_freed(object, s->objsize); c = get_cpu_slab(s, smp_processor_id()); if (likely(page == c->page && c->node >= 0)) { object[c->offset] = c->freelist; c->freelist = object; + stat(c, FREE_FASTPATH); } else __slab_free(s, page, x, addr, c->offset); local_irq_restore(flags); +#endif } void kmem_cache_free(struct kmem_cache *s, void *x) @@ -1840,7 +1985,7 @@ static void init_kmem_cache_cpu(struct kmem_cache *s, struct kmem_cache_cpu *c) { c->page = NULL; - c->freelist = NULL; + c->freelist = (void *)PAGE_MAPPING_ANON; c->node = 0; c->offset = s->offset / sizeof(void *); c->objsize = s->objsize; @@ -1997,6 +2142,7 @@ static struct kmem_cache_node *early_kmem_cache_node_alloc(gfp_t gfpflags, { struct page *page; struct kmem_cache_node *n; + unsigned long flags; BUG_ON(kmalloc_caches->size < sizeof(struct kmem_cache_node)); @@ -2021,7 +2167,14 @@ static struct kmem_cache_node *early_kmem_cache_node_alloc(gfp_t gfpflags, #endif init_kmem_cache_node(n); atomic_long_inc(&n->nr_slabs); - add_partial(n, page); + /* + * lockdep requires consistent irq usage for each lock + * so even though there cannot be a race this early in + * the boot sequence, we still disable irqs. + */ + local_irq_save(flags); + add_partial(n, page, 0); + local_irq_restore(flags); return n; } @@ -2206,7 +2359,7 @@ static int kmem_cache_open(struct kmem_cache *s, gfp_t gfpflags, s->refcount = 1; #ifdef CONFIG_NUMA - s->defrag_ratio = 100; + s->remote_node_defrag_ratio = 100; #endif if (!init_kmem_cache_nodes(s, gfpflags & ~SLUB_DMA)) goto error; @@ -2228,7 +2381,7 @@ error: */ int kmem_ptr_validate(struct kmem_cache *s, const void *object) { - struct page * page; + struct page *page; page = get_object_page(object); @@ -2322,7 +2475,6 @@ void kmem_cache_destroy(struct kmem_cache *s) if (kmem_cache_close(s)) WARN_ON(1); sysfs_slab_remove(s); - kfree(s); } else up_write(&slub_lock); } @@ -2341,7 +2493,7 @@ static struct kmem_cache *kmalloc_caches_dma[PAGE_SHIFT]; static int __init setup_slub_min_order(char *str) { - get_option (&str, &slub_min_order); + get_option(&str, &slub_min_order); return 1; } @@ -2350,7 +2502,7 @@ __setup("slub_min_order=", setup_slub_min_order); static int __init setup_slub_max_order(char *str) { - get_option (&str, &slub_max_order); + get_option(&str, &slub_max_order); return 1; } @@ -2359,7 +2511,7 @@ __setup("slub_max_order=", setup_slub_max_order); static int __init setup_slub_min_objects(char *str) { - get_option (&str, &slub_min_objects); + get_option(&str, &slub_min_objects); return 1; } @@ -2437,7 +2589,8 @@ static noinline struct kmem_cache *dma_kmalloc_cache(int index, gfp_t flags) goto unlock_out; realsize = kmalloc_caches[index].objsize; - text = kasprintf(flags & ~SLUB_DMA, "kmalloc_dma-%d", (unsigned int)realsize), + text = kasprintf(flags & ~SLUB_DMA, "kmalloc_dma-%d", + (unsigned int)realsize); s = kmalloc(kmem_size, flags & ~SLUB_DMA); if (!s || !text || !kmem_cache_open(s, flags, text, @@ -2592,6 +2745,7 @@ EXPORT_SYMBOL(ksize); void kfree(const void *x) { struct page *page; + void *object = (void *)x; if (unlikely(ZERO_OR_NULL_PTR(x))) return; @@ -2601,10 +2755,23 @@ void kfree(const void *x) put_page(page); return; } - slab_free(page->slab, page, (void *)x, __builtin_return_address(0)); + slab_free(page->slab, page, object, __builtin_return_address(0)); } EXPORT_SYMBOL(kfree); +static unsigned long count_partial(struct kmem_cache_node *n) +{ + unsigned long flags; + unsigned long x = 0; + struct page *page; + + spin_lock_irqsave(&n->list_lock, flags); + list_for_each_entry(page, &n->partial, lru) + x += page->inuse; + spin_unlock_irqrestore(&n->list_lock, flags); + return x; +} + /* * kmem_cache_shrink removes empty slabs from the partial lists and sorts * the remaining slabs by the number of items in use. The slabs with the @@ -2874,7 +3041,8 @@ void __init kmem_cache_init(void) #endif - printk(KERN_INFO "SLUB: Genslabs=%d, HWalign=%d, Order=%d-%d, MinObjects=%d," + printk(KERN_INFO + "SLUB: Genslabs=%d, HWalign=%d, Order=%d-%d, MinObjects=%d," " CPUs=%d, Nodes=%d\n", caches, cache_line_size(), slub_min_order, slub_max_order, slub_min_objects, @@ -2931,7 +3099,7 @@ static struct kmem_cache *find_mergeable(size_t size, * Check if alignment is compatible. * Courtesy of Adrian Drzewiecki */ - if ((s->size & ~(align -1)) != s->size) + if ((s->size & ~(align - 1)) != s->size) continue; if (s->size - size >= sizeof(void *)) @@ -3040,8 +3208,9 @@ static int __cpuinit slab_cpuup_callback(struct notifier_block *nfb, return NOTIFY_OK; } -static struct notifier_block __cpuinitdata slab_notifier = - { &slab_cpuup_callback, NULL, 0 }; +static struct notifier_block __cpuinitdata slab_notifier = { + .notifier_call = slab_cpuup_callback +}; #endif @@ -3076,25 +3245,12 @@ void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags, return slab_alloc(s, gfpflags, node, caller); } -static unsigned long count_partial(struct kmem_cache_node *n) -{ - unsigned long flags; - unsigned long x = 0; - struct page *page; - - spin_lock_irqsave(&n->list_lock, flags); - list_for_each_entry(page, &n->partial, lru) - x += page->inuse; - spin_unlock_irqrestore(&n->list_lock, flags); - return x; -} - #if defined(CONFIG_SYSFS) && defined(CONFIG_SLUB_DEBUG) static int validate_slab(struct kmem_cache *s, struct page *page, unsigned long *map) { void *p; - void *addr = page_address(page); + void *addr = slab_address(page); if (!check_slab(s, page) || !on_freelist(s, page, NULL)) @@ -3211,8 +3367,9 @@ static void resiliency_test(void) p = kzalloc(32, GFP_KERNEL); p[32 + sizeof(void *)] = 0x34; printk(KERN_ERR "\n2. kmalloc-32: Clobber next pointer/next slab" - " 0x34 -> -0x%p\n", p); - printk(KERN_ERR "If allocated object is overwritten then not detectable\n\n"); + " 0x34 -> -0x%p\n", p); + printk(KERN_ERR + "If allocated object is overwritten then not detectable\n\n"); validate_slab_cache(kmalloc_caches + 5); p = kzalloc(64, GFP_KERNEL); @@ -3220,7 +3377,8 @@ static void resiliency_test(void) *p = 0x56; printk(KERN_ERR "\n3. kmalloc-64: corrupting random byte 0x56->0x%p\n", p); - printk(KERN_ERR "If allocated object is overwritten then not detectable\n\n"); + printk(KERN_ERR + "If allocated object is overwritten then not detectable\n\n"); validate_slab_cache(kmalloc_caches + 6); printk(KERN_ERR "\nB. Corruption after free\n"); @@ -3233,7 +3391,8 @@ static void resiliency_test(void) p = kzalloc(256, GFP_KERNEL); kfree(p); p[50] = 0x9a; - printk(KERN_ERR "\n2. kmalloc-256: Clobber 50th byte 0x9a->0x%p\n\n", p); + printk(KERN_ERR "\n2. kmalloc-256: Clobber 50th byte 0x9a->0x%p\n\n", + p); validate_slab_cache(kmalloc_caches + 8); p = kzalloc(512, GFP_KERNEL); @@ -3374,7 +3533,7 @@ static int add_location(struct loc_track *t, struct kmem_cache *s, static void process_slab(struct loc_track *t, struct kmem_cache *s, struct page *page, enum track_item alloc) { - void *addr = page_address(page); + void *addr = slab_address(page); DECLARE_BITMAP(map, s->objects); void *p; @@ -3390,7 +3549,7 @@ static void process_slab(struct loc_track *t, struct kmem_cache *s, static int list_locations(struct kmem_cache *s, char *buf, enum track_item alloc) { - int n = 0; + int len = 0; unsigned long i; struct loc_track t = { 0, 0, NULL }; int node; @@ -3421,54 +3580,54 @@ static int list_locations(struct kmem_cache *s, char *buf, for (i = 0; i < t.count; i++) { struct location *l = &t.loc[i]; - if (n > PAGE_SIZE - 100) + if (len > PAGE_SIZE - 100) break; - n += sprintf(buf + n, "%7ld ", l->count); + len += sprintf(buf + len, "%7ld ", l->count); if (l->addr) - n += sprint_symbol(buf + n, (unsigned long)l->addr); + len += sprint_symbol(buf + len, (unsigned long)l->addr); else - n += sprintf(buf + n, "<not-available>"); + len += sprintf(buf + len, "<not-available>"); if (l->sum_time != l->min_time) { unsigned long remainder; - n += sprintf(buf + n, " age=%ld/%ld/%ld", + len += sprintf(buf + len, " age=%ld/%ld/%ld", l->min_time, div_long_long_rem(l->sum_time, l->count, &remainder), l->max_time); } else - n += sprintf(buf + n, " age=%ld", + len += sprintf(buf + len, " age=%ld", l->min_time); if (l->min_pid != l->max_pid) - n += sprintf(buf + n, " pid=%ld-%ld", + len += sprintf(buf + len, " pid=%ld-%ld", l->min_pid, l->max_pid); else - n += sprintf(buf + n, " pid=%ld", + len += sprintf(buf + len, " pid=%ld", l->min_pid); if (num_online_cpus() > 1 && !cpus_empty(l->cpus) && - n < PAGE_SIZE - 60) { - n += sprintf(buf + n, " cpus="); - n += cpulist_scnprintf(buf + n, PAGE_SIZE - n - 50, + len < PAGE_SIZE - 60) { + len += sprintf(buf + len, " cpus="); + len += cpulist_scnprintf(buf + len, PAGE_SIZE - len - 50, l->cpus); } if (num_online_nodes() > 1 && !nodes_empty(l->nodes) && - n < PAGE_SIZE - 60) { - n += sprintf(buf + n, " nodes="); - n += nodelist_scnprintf(buf + n, PAGE_SIZE - n - 50, + len < PAGE_SIZE - 60) { + len += sprintf(buf + len, " nodes="); + len += nodelist_scnprintf(buf + len, PAGE_SIZE - len - 50, l->nodes); } - n += sprintf(buf + n, "\n"); + len += sprintf(buf + len, "\n"); } free_loc_track(&t); if (!t.count) - n += sprintf(buf, "No data\n"); - return n; + len += sprintf(buf, "No data\n"); + return len; } enum slab_stat_type { @@ -3498,7 +3657,6 @@ static unsigned long slab_objects(struct kmem_cache *s, for_each_possible_cpu(cpu) { struct page *page; - int node; struct kmem_cache_cpu *c = get_cpu_slab(s, cpu); if (!c) @@ -3510,8 +3668,6 @@ static unsigned long slab_objects(struct kmem_cache *s, continue; if (page) { if (flags & SO_CPU) { - int x = 0; - if (flags & SO_OBJECTS) x = page->inuse; else @@ -3848,24 +4004,80 @@ static ssize_t free_calls_show(struct kmem_cache *s, char *buf) SLAB_ATTR_RO(free_calls); #ifdef CONFIG_NUMA -static ssize_t defrag_ratio_show(struct kmem_cache *s, char *buf) +static ssize_t remote_node_defrag_ratio_show(struct kmem_cache *s, char *buf) { - return sprintf(buf, "%d\n", s->defrag_ratio / 10); + return sprintf(buf, "%d\n", s->remote_node_defrag_ratio / 10); } -static ssize_t defrag_ratio_store(struct kmem_cache *s, +static ssize_t remote_node_defrag_ratio_store(struct kmem_cache *s, const char *buf, size_t length) { int n = simple_strtoul(buf, NULL, 10); if (n < 100) - s->defrag_ratio = n * 10; + s->remote_node_defrag_ratio = n * 10; return length; } -SLAB_ATTR(defrag_ratio); +SLAB_ATTR(remote_node_defrag_ratio); +#endif + +#ifdef CONFIG_SLUB_STATS + +static int show_stat(struct kmem_cache *s, char *buf, enum stat_item si) +{ + unsigned long sum = 0; + int cpu; + int len; + int *data = kmalloc(nr_cpu_ids * sizeof(int), GFP_KERNEL); + + if (!data) + return -ENOMEM; + + for_each_online_cpu(cpu) { + unsigned x = get_cpu_slab(s, cpu)->stat[si]; + + data[cpu] = x; + sum += x; + } + + len = sprintf(buf, "%lu", sum); + + for_each_online_cpu(cpu) { + if (data[cpu] && len < PAGE_SIZE - 20) + len += sprintf(buf + len, " c%d=%u", cpu, data[cpu]); + } + kfree(data); + return len + sprintf(buf + len, "\n"); +} + +#define STAT_ATTR(si, text) \ +static ssize_t text##_show(struct kmem_cache *s, char *buf) \ +{ \ + return show_stat(s, buf, si); \ +} \ +SLAB_ATTR_RO(text); \ + +STAT_ATTR(ALLOC_FASTPATH, alloc_fastpath); +STAT_ATTR(ALLOC_SLOWPATH, alloc_slowpath); +STAT_ATTR(FREE_FASTPATH, free_fastpath); +STAT_ATTR(FREE_SLOWPATH, free_slowpath); +STAT_ATTR(FREE_FROZEN, free_frozen); +STAT_ATTR(FREE_ADD_PARTIAL, free_add_partial); +STAT_ATTR(FREE_REMOVE_PARTIAL, free_remove_partial); +STAT_ATTR(ALLOC_FROM_PARTIAL, alloc_from_partial); +STAT_ATTR(ALLOC_SLAB, alloc_slab); +STAT_ATTR(ALLOC_REFILL, alloc_refill); +STAT_ATTR(FREE_SLAB, free_slab); +STAT_ATTR(CPUSLAB_FLUSH, cpuslab_flush); +STAT_ATTR(DEACTIVATE_FULL, deactivate_full); +STAT_ATTR(DEACTIVATE_EMPTY, deactivate_empty); +STAT_ATTR(DEACTIVATE_TO_HEAD, deactivate_to_head); +STAT_ATTR(DEACTIVATE_TO_TAIL, deactivate_to_tail); +STAT_ATTR(DEACTIVATE_REMOTE_FREES, deactivate_remote_frees); + #endif -static struct attribute * slab_attrs[] = { +static struct attribute *slab_attrs[] = { &slab_size_attr.attr, &object_size_attr.attr, &objs_per_slab_attr.attr, @@ -3893,7 +4105,26 @@ static struct attribute * slab_attrs[] = { &cache_dma_attr.attr, #endif #ifdef CONFIG_NUMA - &defrag_ratio_attr.attr, + &remote_node_defrag_ratio_attr.attr, +#endif +#ifdef CONFIG_SLUB_STATS + &alloc_fastpath_attr.attr, + &alloc_slowpath_attr.attr, + &free_fastpath_attr.attr, + &free_slowpath_attr.attr, + &free_frozen_attr.attr, + &free_add_partial_attr.attr, + &free_remove_partial_attr.attr, + &alloc_from_partial_attr.attr, + &alloc_slab_attr.attr, + &alloc_refill_attr.attr, + &free_slab_attr.attr, + &cpuslab_flush_attr.attr, + &deactivate_full_attr.attr, + &deactivate_empty_attr.attr, + &deactivate_to_head_attr.attr, + &deactivate_to_tail_attr.attr, + &deactivate_remote_frees_attr.attr, #endif NULL }; @@ -3940,6 +4171,13 @@ static ssize_t slab_attr_store(struct kobject *kobj, return err; } +static void kmem_cache_release(struct kobject *kobj) +{ + struct kmem_cache *s = to_slab(kobj); + + kfree(s); +} + static struct sysfs_ops slab_sysfs_ops = { .show = slab_attr_show, .store = slab_attr_store, @@ -3947,6 +4185,7 @@ static struct sysfs_ops slab_sysfs_ops = { static struct kobj_type slab_ktype = { .sysfs_ops = &slab_sysfs_ops, + .release = kmem_cache_release }; static int uevent_filter(struct kset *kset, struct kobject *kobj) @@ -4048,6 +4287,7 @@ static void sysfs_slab_remove(struct kmem_cache *s) { kobject_uevent(&s->kobj, KOBJ_REMOVE); kobject_del(&s->kobj); + kobject_put(&s->kobj); } /* |